What does "grade" mean?

Grade: In a railroad or highway: (a) The rate of ascent or descent; gradient; deviation from a level surface to an inclined plane; -- usually stated as so many feet per mile, or as one foot rise or fall in so many of horizontal distance; as, a heavy grade; a grade of twenty feet per mile, or of 1 in 264. (b) A graded ascending, descending, or level portion of a road; a gradient.

Additional senses

  1. 2.(Stock Breeding) The result of crossing a native stock with some better breed. If the crossbreed have more than three fourths of the better blood, it is called high grade. At grade, on the same level; -- said of the crossing of a railroad with another railroad or a highway, when they are on the same level at the point of crossing. -- Down grade, a descent, as on a graded railroad. -- Up grade, an ascent, as on a graded railroad. -- Equating for grades. See under Equate. -- Grade crossing, a crossing at grade.
  2. 3.To arrange in order, steps, or degrees, according to size, quality, rank, etc.
  3. 4.To reduce to a level, or to an evenly progressive ascent, as the line of a canal or road.
  4. 5.(Stock Breeding) To cross with some better breed; to improve the blood of.

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